The invention relates to a disc brake, particularly for commercial vehicles, having a single-part or multi-part caliper, which reaches over a brake disc and can be swivelled or slid relative to a wheel axle or hub, and having a brake application device arranged in the caliper for applying the brake.
From European Patent document EP 0 688 404 B1, a sliding-caliper disc brake is known, where a brake application device with a rotary lever is arranged on one side of the caliper, which lever is disposed to be pivoted about an axis of rotation extending parallel to the plane of the brake disc. Facing the brake disc, this rotary lever rests, by means of an eccentric, against a transverse member which is slidably guided with respect to the brake disc and in which two adjusting screws provided with an external thread are adjustably screwed in a parallel arrangement.
From German Patent document DE 36 10 569 C2, a sliding-caliper disc brake is also known, where a rotary lever has one eccentric respectively at two ends, each eccentric engaging with a set bolt in order to press a brake shoe or a brake pad against the brake disc when a piston rod is actuated by a cylinder which can be acted upon by a pressure medium.
In this case, the sliding-caliper brake caliper is designed such that, by means of the sliding path, the working stroke of the brake during each braking as well as the maximal wear displacement of the brake pads, that is, the adjusting path of the brake, can be bridged. For adjusting the brake pad wear, an adjusting device is used, which is arranged on one side of the brake disc.
Swivellable disc brakes of the above-mentioned type are also known. Similar to the above-mentioned sliding caliper disc brakes, here the swivelling angle must be dimensioned such that it becomes possible, in the area of the brake pads, to bridge the path of the working stroke in order to place the reaction-side brake pad against the brake disc and to compensate the brake pad wear occurring over time by means of the swivelling of the caliper. In this case, the caliper has the task of absorbing the tension forces upon the brake pads; of simultaneously guiding the brake pads; and of transmitting their circumferential forces by way of the fastening and pivot bearing of the caliper to the axle. A disadvantage of such hinged-caliper brakes is the swivelling-out of the caliper mainly at a full wear displacement. This disadvantage becomes particularly clear on the disc side situated opposite the caliper bearing, requiring a smaller outside disc diameter and a smaller brake pad thickness in comparison to fixed-caliper or sliding-caliper brakes.
In light of this background, it is an object of the invention to further develop a disc brake of the above-mentioned type such that a particularly robust and maintenance-free design of the swivelling mechanism or swivel bearing of the caliper is implemented, in which case only the working stroke has to be moved.
The invention achieves this task by providing a disc brake, having: a) a one-part or multi-part caliper, which straddles a brake disc and can be swivelled or slid relative to a wheel axle or wheel hub; b) a brake application device arranged in the caliper for applying the brake; c) at least one adjusting device, respectively, on each side of the brake disc, and preferably one electromotive or mechanical drive respectively acting upon the adjusting device; d) wherein the caliper has supporting elements particularly on its lower side pointing toward the wheel axle in the installed condition, and wherein bearing housings are arranged on the wheel axle or wheel hub; and e) wherein at least one elastically deformable intermediate element is arranged between the bearing housing and the associated supporting element, which intermediate element engages in at least one bearing housing. The supporting element is, in each case, movable relative to the bearing housing such that the swivelling angle or the sliding path of the caliper permits a bridging of the maximal working stroke of the disc brake in the area of the brake pads.
The invention provides a disc brake, particularly a pneumatically operated or electromechanically operated disc brake, in the case of which at least one adjusting device, respectively, is arranged on both sides of the brake disc. In particular, at least one adjusting rotary device is arranged on each side of the brake disc, preferably with an electromotive or mechanical drive acting upon the adjusting rotating device.
In this case, the caliper, particularly at a lower side pointing toward the wheel axle in an installed position, is provided with one, preferably two bearing housings, and at least one or two supporting elements are arranged on the wheel axle or hub.
In addition, at least one elastically deformable intermediate element may be respectively provided or arranged between the bearing housing and the supporting element, which intermediate element engages in the at least one bearing housing at the caliper.
As an alternative, it is also contemplated that the caliper has supporting elements on its lower side pointing toward the wheel axle in the installed position, and bearing housings are arranged at the wheel axle or hub, in which case at least one elastically deformable intermediate element is respectively provided/arranged between the bearing housing and the supporting element, which intermediate element engages in the at least one bearing housing.
In the case of this type of sliding or swivel bearing, as a result of the adjusting devices being provided on both sides of the brake disc, the brake pad wear need not be compensated by the sliding or swivelling movement but rather by the two adjusting devices which, in the case of wear, advance the brake pads on both sides of the brake disc closer toward the brake disc. As a result, it becomes possible to limit the sliding path or the swivelling angle of the hinged caliper such that in each case only the maximal working stroke can be bridged in the area of the brake pad via the swivelling movement.
The supporting element can, in each case, preferably be moved relative to the bearing housing such that the swivelling angle or the sliding path of the caliper permits a bridging of the maximal working stroke of the disc brake in the area of the brake pads.
Particularly preferably, the supporting elements, in each case, engage in one of the bearing housings, the elastic intermediate elements each being arranged between the supporting elements and the bearing housings. This is a constructively easily implementable variant of the invention, which can be supplemented particularly advantageously in that the elastic intermediate elements have a bush shape and/or consist of a cost-effective elastomer.
Expediently, two of the supporting elements are arranged on—particularly shaped onto—the wheel axle or hub, especially on an axle ring. It can be implemented in a constructively simple manner and is cost-effective for the supporting elements to have a bolt-shaped construction and to be shaped onto the wheel axle or wheel hub by using one of their ends.
This can optionally also be combined with a displaceable disc, which is arranged on the wheel axle, to be displaceable by a portion of the working stroke. This permits an even smaller sizing of the sliding path or of the swivelling angle.
Further, as a result of the elastic bearing between the bearing housing and the supporting element, a “pivot bearing” in the actual sense of the word is avoided in the case of the hinged caliper, which permits, on the one hand, a cost-effective implementation of the hinged-caliper function and, on the other hand, a particularly robust design.
In the case of a sliding-caliper brake, it is expedient for the bearing recesses, the supporting element and the elastic intermediate element to each be aligned such that, in each case, an elastic bearing is constructed which is aligned coaxially with respect to the brake disc axis.
In contrast, in the case of a hinged-caliper brake, it is advantageous to construct one elastic bearing, respectively, which is aligned perpendicular to the brake disc axis.
Preferably, the supporting element can in each case be moved relative to the bearing housing such that the swivelling angle or the sliding angle of the caliper (preferably only) permits a bridging of the maximal working stroke of the disc brake in the area of the brake pads.
In that the free ends of two of the supporting elements are arranged as an extension of a chord through the axle ring at the two intersections of the chord with the axle rings and point away from one another with their free ends, a construction can be created which is as stable as possible and nevertheless, by using simple devices, the necessary swivelling motion can be implemented.
Particularly preferably, the supporting elements have radial contact surfaces which, with a small play, are in contact, which directly transmits the radial forces, with corresponding opposite surfaces of the bearing housings. This results in a particularly good support against forces which may rotate the caliper.
In another, particularly preferred, embodiment, at least one intermediate element is constructed in a cost-effective manner as a rubber-metal composite part.
The bearing housing and the supporting element may definitely be in contact in areas. It is important that, in sections, an elastic intermediate element is nevertheless arranged between the two elements.
Advantageous further developments of the invention are described and claimed herein.